Triggers for Freezing of Gait in Individuals with Parkinson's Disease: A Systematic Review

BackgroundFreezing of Gait (FOG) is a motor symptom frequently observed in advanced Parkinsons disease. However, due to its paroxysmal nature and diverse presentation, assessing FOG in a clinical setting can be challenging. Before FOG can be fully investigated, it is critical that a reliable experimental setting is established in which FOG can be evoked in a standardised manner, but the efficacy of various gait tasks and triggers for eliciting FOG remains unclear. ObjectivesThis study aimed to conduct a systematic review of the existing literature and evaluate the available evidence for the relationship between specific motor tasks, triggers, and FOG episodes in individuals with Parkinsons disease (PwPD). MethodsWe conducted a literature search on four online databases (PubMed, Web of Science, EMBASE, and Cochrane Library) using the keywords "Parkinsons disease," "Freezing of Gait," and "triggers." A total of 128 articles met the inclusion criteria and were included in our analysis. ResultsThe review found that a wide range of gait tasks were employed in gait assessment studies on PD patients. However, three tasks (turning, dual tasking, and straight walking) were the most frequently used. Turning (28%) appears to be the most effective trigger for eliciting FOG in PwPD, followed by walking through a doorway (14%) and dual tasking (10%). ConclusionsThis review thereby supports the use of turning especially 360 degrees as a reliable trigger for FOG in PwPD. This could be beneficial to clinicians during clinical evaluations and researchers who wish to assess FOG in a laboratory environment.